Electrically heated sauna stove



Aug. 22, 1967 J. J. FINN 3,337,715

ELECTRICALLY HEATED SAUNA STOVE Filed June 24, 1965 2 SheetsShet 1 INVENTOR. f j 0 United States Patent 3,337,715 ELECTRICALLY HEATED SAUNA STOVE John .1. Finn, Erie, Pa., assignor of one-half to Glenn Electric Heater Corporation, Erie, Pa, a corporation of Pennsylvania Filed June 24, 1965, Ser. No. 466,573 3 Claims. (Cl. 219-367) ABSTRACT OF THE DISCLOSURE A sauna stove of triangular, horizontal, cross section having an angular back wall fitting the corner of a sauna room and a front wall extending across the edges of the back wall and having an air outlet at its upper end. The top of the stove is closed by a triangular rock pan. The heated air enters the room through two convection paths, one path through the center of a vertical pipe below the rock pan and open at its upper and lower ends and the other path between the outside of the pipe and the front and back walls. An elongated electric heating element having one or more axially extending loops is arranged within the pipe and radiates to the pipe and to the bottom of the rock pan. The air heats the room to the desired temperature while the radiant heat applied to the rock pan heats it well above the boiling pomt of water so it can be used to generate steam. Over heating is prevented by a thermostat having a sensing element arranged in the space between the pipe and the front and back walls of the stove.

This invention is an electrically heated sauna stove for a sauna bath compartment which typically consists of a wood panelled room. The stove has the function of supplying dry heat to maintain the desired room temperature and of preheating stones for generating steam at the conclusion of the bath.

The stove is of triangular cross section having an angular back wall and a front wall extendingacross the edges of the back wall. The upper end of the stove is closed by a triangular rock pan and there is an outlet for heated air in the front wall below the rock pan. The electric heater has one or more elongated, axially extending loops arranged at the center of a pipe open at its upper and lower ends. The heater radiates to the bottom of the rock pan and to the pipe and the air is heated by conduction currents flowing up through the center of the pipe and up through the space between the pipe and the front and back walls. Over heating such as might be caused by blocking of the hot air outlet from the stove is prevented by a thermostat having its sensing element in the space between the pipe and the front and back walls.

In the drawing, FIG. 1 is a perspective of a sauna stove, FIG. 2 is a front elevation partly broken away, FIG. 3 is a section on line 3-3 of FIG. 2, and FIG. 4 is a section on line 4-4 of FIG. 3.

The sauna stove 1 is wall mounted in the corner of the sauna bath with the lower end 2 spaced above the floor to provide an air inlet. The room temperature is controlled by a thermostat 3. Toward the top of the front wall 4 of the stove is a hot air outlet grill 5. A stainless steel rock pan 6 fits in the top of the stove and holds the stones which are preheated well above steaming temperature. At the end of the dry heat cycle of the bath, a

small quantity of water is thrown into the rock pan,

producing steam for the conclusion of the bath. The top of the stove is substantially table height so there is some danger that a towel may be placed over the stove and block the hot air outlet 5. Suitable over-temperature 3,337,715 Patented Aug. 22, 1967 protection is provided so that fires will not be caused under these circumstances.

The back of the stove has double angular walls 7 and 8 spaced from each other to provide a flue 9 open at the top and bottom. Toward the top, the wall 7 is suitably slotted to receive the upper ends 10 of brackets 11 fastened to the wall. At the lower end, the wall 7 is provided with brackets 12 which are screwed to the wall. This keeps the wall 7 spaced a safe distance from the wall of the sauna bath and prevents any fire hazard. The bottom wall 13 is connected across the lower end of the angular wall 8, providing an air space 14 at the front and an air space 15 at the back. Perforations 16 provide additional air flow if desired. Fixed to the upper side of the bottom wall 13 is a plate 17 having upstanding triangular ears 18 fixed to the lower end of a pipe 19. The upper end of the pipe is suitably conected to the wall 8 by a brace 20. The lower end of the pipe 19, as shown at 21, is spaced above the plate 17 providing air inlets between the ears 18. The upper end of the pipe 19 terminates slightly below the grill 5 and is directly presented to the bottom of the rock pan 6.

Bolted to the under side of the bottom wall 13 is an outlet box 22 containing an over-temperature cutout thermostat 23 and terminals 24 for a vertical elongated electric heating element 25 having one or more axially extending loops 26 at the enter of the pipe 19. The electric heating element radiates heat to the pipe 19 and to the bottom of the rock pan 6. Convection currents both inside and outside the pipe 19 discharge heat through the grill 5, thereby maintaining the sauna room at the desired temperature. There are also convection currents through the flue 9 between the walls 7 and 8 which prevent overheating of the walls and there may be additional convection currents in the space between the wall 7 and the walls of the sauna room, eliminating any fire hazard.

The over-temperature cutout Z3 is associated with a capillary tube 27 which is filled with a temperature sensitive liquid. The tube 27 is suitably supported, for example by being formed in a self supporting coil above the bottom Wall 13 of the stove and adjacent the lower end of the pipe 19. During normal operation, when the grill 5 is open the temperature of the capillary 27 is relatively low and the over-temperature cutout 23 is closed. If the grill 5 is blocked, the normal convection currents are stopped and the temperature of the capillary 27 rises quickly enough to cut off the heating elements before dangerous overheating can occur.

The radiant heat from the heating element 25 provides quick heating of the rock pan 6. The temperature of the stones in the rock pan is well above the boiling point of water. In order to prevent burning due to accidental contact with the hot edges of the rock pan, these edges are covered with a silicone rubber bead 28 which eliminates danger of burning due to accidental contact.

What is claimed as new is:

1. A sauna room having corner walls, a sauna stove having a body of triangular horizontal cross section open at the top and bottom, said body having a front wall with a hot air outlet adjacent the top and an angular back wall extending from opposite sides of the front wall, means for mounting said back wall on and in spaced relation to said corner walls of the sauna room to provide a flue open at top and bottom, a triangular rock pan above said outlet and fitting in and closing the top of said body, said rock pan being open at its top, an upstanding pipe open at its upper and lower ends, means for supporting the pipe so the pipe is spaced from the back and front walls to provide paths discharging through the hot air outlet for convection air currents within the pipe and between the pipe and the front and back walls and said pipe having its upper end presented to and spaced below said rock pan, an elongated electric heating element, means for supporting the heating element within and in spaced relation to the pipe, said heating element having at least one axially extending loop radiating heat to the inner surface of the pipe and to the rock pan, means for connecting the heating element to a source of electric power, and a thermostat control for said heating element having a sensing element, means for supporting the sensing element in the space between the lower end of the pipe and said back and front walls for preventing overheating in case of blocking said outlet.

2. A sauna room having corner walls, a sauna stove having a body of triangular horizontal cross section open at top and bottom, said body having a front wall with a hot air outlet adjacent the top and an angular back wall extending from opposite sides of the front wall, means for mounting said back wall on and in spaced relation to said corner walls of the sauna room to provide a flue open at top and bottom, a triangular rock pan above said outlet and fitting in and closing the top of said body, said rock pan being open at its top, an upstanding pipe open at its upper and lower ends, means for supporting the pipe so the pipe is spaced from the back and front walls to provide paths discharging through the hot air outlet for convection air currents within the pipe and between the pipe and the front and back walls and said pipe having its upper end presented to and spaced below said rock pan, an elongated electric heating element, means for supporting the heating element within and in spaced relation to the pipe, said heating element having at least one axially extending loop radiating heat to the inner surface of the pipe and to the rock pan, and means for connecting the heating element to a source of electric power.

3. A sauna stove having a body of triangular horizontal cross section open at top and bottom, said body having a front wall with a hot air outlet adjacent the top and an angular back wall extending from opposite sides of the front wall and adapted to fit in the corner of a sauna room, a triangular rock pan above said outlet and fitting in andclosing the top of said body, said rock pan being open at its top, a bottom wall extending across and fixed to the back wall and partially closing the lower end of the body, an outlet box fixed to the under side of said bottom wall, a supporting bracket having arms upstanding from said bottom wall, a vertical pipe having its lower end fixed to said arms, said pipe being open at its upper and lower ends and spaced from the back and front walls to provide paths for convection air currents within the pipe and between the pipe and the walls and having its lower end spaced above said bottom wall and its upper end presented to and spaced from said rock pan, a vertical elongated electric heating element spaced within said pipe and having its lower end mounted on said outlet box, means for connecting the heating element to a source of electric power, said heating element radiating heat to the inner surface of the pipe and to the rock pan, and a thermostat control for said heating element, said said thermostat control being located within the outlet box and having a sensing element in the space between the lower end of the pipe and said walls for preventing overheating in case of blocking said outlet.

References Cited UNITED STATES PATENTS 1,900,956 3/ 1933 Somersall 219362 2,405,783 8/ 1946 Gardenhour 219-370 2,654,018 9/1953 Sandberg. 2,709,214 5/ 1955 Engdahl et al. 3,066,668 12/ 1962 Richter. 3,275,800 9/1966 Kuoppamaki et al. 219-378 X FOREIGN PATENTS 958,137 9/1949 France. 1,262,647 4/ 1961 France.

616,057 1/ 1949 Great Britain.

ANTHONY BARTIS, Primwry Examiner. 

3. A SAUNA STOVE HAVING A BODY OF TRIANGULAR HORIZONTAL CROSS SECTION OPEN AT TOP AND BOTTOM, SAID BODY HAVING A FRONT WALL WITH A HOT AIR OUTLET ADJACENT THE TOP AND AN ANGULAR BACK WALL EXTENDING FROM OPPOSITE SIDES OF THE FRONT WALL AND ADAPTED TO FIT IN THE CORNER OF A SAUNA ROOM, A TRIANGULAR ROCK PAN ABOVE SAID OUTLET AND FITTING IN AND CLOSING THE TOP OF SAID BODY, SAID ROCK PAN BEING OPEN AT ITS TOP, A BOTTOM WALL EXTENDING ACROSS AND FIXED TO THE BACK WALL AND PARTIALLY CLOSING THE LOWER END OF THE BODY, AN OUTLET BOX FIXED TO THE UNDER SIDE OF SAID BOTTOM WALL, A SUPPORTING BRACKET HAVING ARMS UPSTANDING FROM SAID BOTTOM WALL, A VERTICAL PIPE HAVING ITS LOWER END FIXED TO SAID ARMS, SAID PIPE BEING OPEN AT ITS UPPER AND LOWER END SPACED FROM THE BACK AND FRONT WALLS TO PROVIDE PATHS FOR CONVECTION AIR CURRENTS WITHIN THE PIPE AND BETWEEN THE PIPE AND THE WALLS AND HAVING ITS LOWER END SPACED ABOVE SAID BOTTOM WALL AND ITS UPPER END PRESENTED TO AND SPACED FROM SAID ROCK PAN, A VERTICAL ELONGATED ELECTRIC HEATING ELEMENT SPACED WITHIN SAID PIPE AND HAVING IT LOWER END MOUNTED ON SAID OUTLET, MEANS FOR CONNECTING THE HEATING ELEMENT TO A SOURCE OF ELECTRICAL POWER, SAID HEATING ELEMENT RADIATING HEAT TO THE INNER SURFACE OF THE PIPE AND TO THE ROCK PAN, AND A THERMOSTAT CONTROL FOR SAID HEATING ELEMENT, SAID SAID THERMOSTAT CONTROL BEING LOCATED WITHIN THE OUTLET BOX AND HAVING A SENSING ELEMENT IN THE SPACE BETWEEN THE LOWER END OF THE PIPE AND SAID WALLS FOR PREVENTING OVERHEATING IN CASE OF BLOCKING SAID OUTLET. 